Battery controller and method for controlling a battery

Abstract

A battery controller for charging and discharging a plurality of batteries is disclosed. The battery controller has a plurality of direct current to direct current (DC to DC) converters connected to each other in series. Each battery of a plurality of batteries is electrically connectable to a respective DC to DC converter. A co-ordinator connected to each of the plurality of DC to DC converters controls charging and discharging of the battery electrically connected to the respective converter. The coordinator can also control charging and discharging of any one of the batteries to ensure that the battery retains sufficient electrical capacity, and, to increase the longevity of the respective batteries. Because each battery is electrically connected to a respective DC to DC converter, the energy from one battery can be used to charge another battery in order to monitor battery characteristics including energy capacity of each battery. Each of the DC to DC converters is selected to operate preferably below 30 volts while the total voltage of the entire battery system can be much more than 30 volts depending on the number of DC to DC converters placed in series.

1 . An apparatus for charging and discharging a plurality of batteries, said apparatus comprising 
 a plurality of batteries;    a plurality of direct current to direct current (DC to DC) converters, each DC to DC converter comprising load-side terminals and battery-side terminals, with the load-side terminals of the DC to DC converters being connected to each other in series, and, each battery of the plurality of batteries is electrically connected to the battery-side terminals of a respective DC to DC converter;    a co-ordinator connected to each of the plurality of DC to DC converters for controlling charging and discharging of the battery electrically connected to the respective converter; and    wherein the series connected load-side terminals of the plurality of DC to DC converters are electrically connected to at least one load and the co-ordinator co-ordinates the transfer of electrical power from the plurality of batteries to the one or more loads.    
   
   
       2 . The apparatus for charging and discharging a plurality of batteries as defined in  claim 1  wherein each of the plurality of DC to DC converters operate in the range of 5 volts to 30 volts.  
   
   
       3 . The apparatus for charging and discharging a plurality of batteries as defined in  claim 2  wherein each of the plurality of DC to DC converters operate in the range of 10 volts to 25 volts.  
   
   
       4 . The apparatus for charging and discharging a plurality of batteries as defined in  claim 3  wherein each of the plurality of DC to DC converters operate in the range of 15 volts to 22 volts.  
   
   
       5 . The apparatus for charging and discharging a plurality of batteries as defined in  claim 2  wherein: 
 N represents the total number of DC to DC converters in the plurality of DC to DC converters;    V total  represents the expected total voltage of the nominal discharge of the apparatus;    the voltage of any one DC to DC converter is approximately V total /N; and    V total /N is less than or approximately equal to 30 volts.    
   
   
       6 . The apparatus for charging and discharging a plurality of batteries as defined in  claim 1  further comprising a current monitor for monitoring the current passing through the plurality of DC to DC converters connected in series.  
   
   
       7 . The apparatus for charging and discharging a plurality of batteries as defined in  claim 1  further comprising a voltage monitor for detecting the total voltage across the series connected load-side terminals of the plurality of DC to DC converters.  
   
   
       8 - 10 . (canceled)  
   
   
       11 . A method for charging and discharging a plurality of batteries, said method comprising: 
 providing a plurality of n batteries, where n is an integer greater than 1;    providing a plurality of n DC to DC converters, with each converter comprising load-side terminals and battery-side terminals;    electrically connecting the battery-side terminals of each DC to DC converter of the plurality of DC to DC converters to a respective battery of the plurality of batteries;    electrically connecting a co-ordinator to each of the plurality of DC to DC converters for controlling, charging and discharging each of the respective batteries; and    wherein the load-side terminals of the plurality of DC to DC converters are electrically connected to each other in series and the co-ordinator co-ordinates transfer of electrical power from the respective batteries to one or more loads through the series connected load-side terminals of the plurality of DC to DC converters.    
   
   
       12 . An apparatus for providing electrical power, the apparatus comprising: 
 a plurality of fuel-less batteries structured to discharge and thereby supply electrical power;    a first battery power converter comprising battery-side terminals and load-side terminals, with the battery-side terminals of the first battery power converter being connected across at least one fuel-less battery of the plurality of fuel-less batteries; and    a second battery power converter comprising battery-side terminals and load-side terminals, with the battery-side terminals of the second battery power converter being connected across at least one fuel-less battery of the plurality of fuel-less batteries and with the load-side terminals of the first and second battery power converters being electrically connected to each other in series.    
   
   
       13 . The apparatus of  claim 12  wherein: 
 each of the plurality of batteries outputs direct current power;    the first battery power converter is a DC to DC converter; and    the second battery power converter is a DC to DC converter.    
   
   
       14 . The apparatus of  claim 12  wherein the battery-side terminals of the first battery power converter and the battery-side terminals of the second battery power converter are connected across non-identical sets of fuel-less batteries of the plurality of fuel-less batteries.  
   
   
       15 . The apparatus of  claim 14  wherein: 
 the battery-side terminals of the first battery power converter are connected across a first fuel-less battery of the plurality of batteries; and    the battery-side terminals of the second battery power converter are connected across a second fuel-less battery of the plurality of batteries.    
   
   
       16 . The apparatus of  claim 14  further comprising at least one additional battery power converter, wherein: 
 the at least one additional battery power converter each comprises battery-side terminals and load-side terminals; and    the battery-side terminals of each of the first battery power converter, the second battery power converter and each additional battery power controller being respectively connected across a unique battery from the plurality of fuel-less batteries.    
   
   
       17 . The apparatus of  claim 12  wherein the first and second battery power converters are voltage converters.  
   
   
       18 . The apparatus of  claim 12  wherein the first and second battery power converters are current converters.  
   
   
       19 . The apparatus of  claim 12  wherein the first battery power converter comprises bypass circuitry to allow the passage of electrical power through the first battery power converter even in the absence of power supplied at the battery-side terminals of the first battery power converter.  
   
   
       20 . An apparatus for storing and discharging electrical power, the apparatus comprising: 
 a plurality of rechargeable batteries structured to store and discharge electrical power;    a first battery power converter comprising battery-side terminals and load-side terminals, with the battery-side terminals of the first battery power converter being connected across at least one rechargeable battery of the plurality of rechargeable batteries; and    a second battery power converter comprising battery-side terminals and load-side terminals, with the battery-side terminals of the second battery power converter being connected across at least one rechargeable battery of the plurality of rechargeable batteries and with the load-side terminals of the first and second battery power converters being electrically connected to each other in series.    
   
   
       21 . The apparatus of  claim 20  further comprising: 
 a coordinator component structured and located to allow selective charging and discharging of the rechargeable batteries by selectively controlling the operation of the first and second battery power converters.    
   
   
       22 . The apparatus of  claim 21  wherein the coordinator component controls the selective charging and discharging of the rechargeable batteries so that the first and second batteries discharge at substantially the same rate with respect to the respective capacities of the batteries.  
   
   
       23 . The apparatus of  claim 20  wherein the first and second battery power converters are structured as DC to DC converters with buck-boost operation.  
   
   
       24 - 29 . (canceled)